Pedro Garzon’s scientific contributions

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Publications (2)


Figure 2: A schematic of the baseline GeoGAN model. The generation of the map is conditioned on the satellite image along with some optional noise. The discriminator is also supplied with the conditional information from the satellite image embedding. One architecture we used is as follows (with c(x x y x z) sn referring to a convolution with a z filters of size x * y and a stride of n, cT(x x y x z) sn is the same with transposed convolutions, and lr referring to a a leaky rely layer): Encoder: input=batchx64x64x3; layers = c(3x3x1024) s2, lr, c(3x3x512) s2, lr c(3x3x256) s2, lr, c(3x3x128) s2, lr, c(4x4x512) s1, batchnorm, lr; output= c(batchx1x1x512) Noise: input=batchx64x64x3; element wise add noise; output=batchx64x64x3 Generator: input=batchx1x1x512; layers cT(4x4x1024) s1, lr, cT(8x8x512) s2, lr, cT(3x3x128) s2, lr, cT(3x3x32) s2, lr, cT(3x3x64) s2; output=batchx64x64x3 Discriminator: input=batchx64x64x3; c(3x3x128) s2, lr, c(3x3x256) s2, lr, c(3x3x512) s2, lr, c(3x3x1024) s2, lr, c(4x4x512) s1, lr, concatenate 512 activation units with embedding of sat image, fully connected layer with 512 outputs, lr, fully connected layer, sigmoid. Convolution padding is omitted for brevity.
Figure 4: The generator, discriminator and reconstruction losses of the conditional GAN with the encoder and only the reconstruction loss trained on the dataset we generated. The discriminator is very quickly learning to tell real maps from fake maps and the Generator and discriminator losses saturate at their current points.
Figure 5: Loss curves over 14 epochs of the GAN without an encoder trainded with GAN, reconstruction and style loss on the CycleGAN dataset. The image quality improves after 3-4 epochs when the reconstruction and style losses start to plateau.
Figure 6: A sample of 9 maps generated by GeoGAN-Model 3 trained on the CycleGAN dataset.
Figure 7: The discriminator and generator loss of the GeoGAN encoder trained on MNIST to evaluate whether the model can capture a simple distribution like handwritten digits.

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GeoGAN: A Conditional GAN with Reconstruction and Style Loss to Generate Standard Layer of Maps from Satellite Images
  • Preprint
  • File available

February 2019

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1,312 Reads

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1 Citation

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Pedro Garzon

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Noa Glaser

Automatically generating maps from satellite images is an important task. There is a body of literature which tries to address this challenge. We created a more expansive survey of the task by experimenting with different models and adding new loss functions to improve results. We created a database of pairs of satellite images and the corresponding map of the area. Our model translates the satellite image to the corresponding standard layer map image using three main model architectures: (i) a conditional Generative Adversarial Network (GAN) which compresses the images down to a learned embedding, (ii) a generator which is trained as a normalizing flow (RealNVP) model, and (iii) a conditional GAN where the generator translates via a series of convolutions to the standard layer of a map and the discriminator input is the concatenation of the real/generated map and the satellite image. Model (iii) was by far the most promising of three models. To improve the results we also added a reconstruction loss and style transfer loss in addition to the GAN losses. The third model architecture produced the best quality of sampled images. In contrast to the other generative model where evaluation of the model is a challenging problem. since we have access to the real map for a given satellite image, we are able to assign a quantitative metric to the quality of the generated images in addition to inspecting them visually. While we are continuing to work on increasing the accuracy of the model, one challenge has been the coarse resolution of the data which upper-bounds the quality of the results of our model. Nevertheless, as will be seen in the results, the generated map is more accurate in the features it produces since the generator architecture demands a pixel-wise image translation/pixel-wise coloring. A video presentation summarizing this paper is available at: https://youtu.be/Ur0flOX-Ji0

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GeoGAN: A Conditional GAN Generate Standard Layer of Maps from Satellite Images

December 2018

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4,570 Reads

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58 Citations

Automatically generating maps from satellite images is an important task. There is a body of literature which tries to address this challenge. We created a more expansive survey of the task by experimenting with different models and adding new loss functions to improve results. We created a database of pairs of satellite images and the corresponding map of the area. Our model translates the satellite image to the corresponding standard layer map image using three main model architectures: (i) a conditional Generative Adversarial Network (GAN) which compresses the images down to a learned embedding, (ii) a generator which is trained as a normalizing flow (RealNVP) model, and (iii) a conditional GAN where the generator translates via a series of convolutions to the standard layer of a map and the discriminator input is the concatenation of the real/generated map and the satellite image. Model (iii) was by far the most promising of three models. To improve the results we also added a reconstruction loss and style transfer loss in addition to the GAN losses. The third model architecture produced the best quality of sampled images. In contrast to the other generative model where evaluation of the model is a challenging problem. since we have access to the real map for a given satellite image, we are able to assign a quantitative metric to the quality of the generated images in addition to inspecting them visually. While we are continuing to work on increasing the accuracy of the model, one challenge has been the coarse resolution of the data which upper-bounds the quality of the results of our model. Nevertheless, as will be seen in the results, the generated map is more accurate in the features it produces since the generator architecture demands a pixel-wise

Citations (2)


... However, these approaches predominantly emphasize the intrinsic features of images while neglecting the relevance and complementarity of geographical features within remote sensing images, leading to maps that inadequately represent intricate geographical features. Various GAN-based map generation methods, such as GeoGAN [5], SMAPGAN [6], and CreativeGAN [7], have improved map generation effects to some extent. Nonetheless, these methods are confined to single-level map generation, employing single-level maps as samples during training and generation. ...

Reference:

C2GM: Cascading Conditional Generation of Multi-scale Maps from Remote Sensing Images Constrained by Geographic Features
GeoGAN: A Conditional GAN Generate Standard Layer of Maps from Satellite Images

... This loss is used as an additional loss function of generator and discriminator to measure the degree of difference between the original graph and the generated graph. GeoGAN (Ganguli et al. 2019) proposed style losses and reconstruction losses to generators and discriminators to force the generated graph to have similar styles and textures to the original. LE-GAN (Fu et al. 2022) added identity invariant loss, and trained the generator and discriminator by extracting feature vectors from the generated graph and the original graph to ensure the identity consistency between the generated graph and the original graph. ...

GeoGAN: A Conditional GAN with Reconstruction and Style Loss to Generate Standard Layer of Maps from Satellite Images